The present invention relates generally to electrical switch apparatus, and more particularly to a high voltage multi-position switch having novel switch contacts and interchangeable contact supports.
High voltage multi-position switches, and particularly such switches employing means for effecting snap-action movement of switch contacts to obtain both load interruption and close into fault operation, are generally known. See, for example, U.S. Pat. Nos. 3,330,919, 3,403,565, 3,519,970, 3,959,616 and 4,095,065, all of which are assigned to the assignee of the present invention. These high voltage multi-position switches can generally be characterized as having a casing in which one or more sets or banks of movable switch contacts are mounted and which, in the case of two position switches, are movable between closed circuit and open circuit conditions. In the case of three position switches, the movable switch contacts are movable between either of two closed contact positions and a neutral or open circuit condition.
In the switches disclosed in U.S. Pat. Nos. 3,478,185, 3,959,616 and 4,095,065, the movable contacts take the form of bifurcated conductive contact supports having pairs of spring contacts mounted on their bifurcated ends to receive fixed switch contact blades when in closed circuit relation. The bifurcated contact supports are mounted on nonconductive rocker arms or plates and have their ends opposite the bifurcated ends connected through bolt clamps and associated braid connectors to bushing conductors defining switch service entrances. The fixed or stationary contact bars are similarly connected to a bus bar and associated bushing conductors through braid conductors and associated bolt clamps and the like. While the rocker arms or plates of the type employed in the aforementioned patents to support the movable contacts have proven relatively satisfactory in operation, they do not readily lend themselves for use in selective interchangeable support of both fixed and movable contacts so that different types of contact supports are required for the fixed and movable switch contacts. Further, the braid conductors and associated bolt clamp connections as have heretofore been employed in high voltage switches are relatively labor intensive thereby contributing significantly to the cost of manufacture.